The present invention provides a multi-layer co-extrusion blow-molded bottle and a preparation method and application thereof. The preparation method comprises the following steps: carrying out multi-layer co-extrusion injection blow molding, demolding and heat treatment on a cycloolefin compound and nylon to obtain the multi-layer co-extrusion blow-molded bottle. The multi-layer co-extrusion blow-molded bottle comprises a water vapor barrier layer and an oxygen barrier layer, the water vapor barrier layer comprises a cycloolefin compound, the oxygen barrier layer comprises nylon, and the ratio of the thickness of the water vapor barrier layer to the thickness of the oxygen barrier layer is ≥ 4:1. The multi-layer co-extrusion blow-molded bottle provided in the present invention has both water vapor barrier performance and oxygen barrier performance, is prepared by one-step multi-layer co-extrusion injection blow molding without interlayer separation, and has low energy consumption and high efficiency in the preparation process.

Country Code: CN

Application Number: CN202510253737.2